1. Field of the Invention
The present invention relates to a flat panel display, and more particularly to a flat panel display having enhanced thermal dissipation uniformity.
2. Discussion of Related Art
Flat panel displays such as a liquid crystal display (LCD), a plasma display panel (PDP) and, in particular, an electron emission display (EED) have been developed and put to practical use.
The EED has been highlighted as a promising next generation display with regard to view angle, high speed response, high brightness, high definition and thinness.
The EED is typically formed of in triode structure having a cathode electrode, an anode electrode and a gate electrode. More specifically, the cathode electrode being commonly used as a scan electrode is formed on a substrate, and an insulating layer with a hole and the gate electrode being commonly used as a data electrode are stacked on the cathode electrode. An emitter, which is an electron emission source, is formed inside of the hole to contact with the cathode electrode.
In general, the EED has schemes of using a hot cathode and a cold cathode as an electron source. As the electron emission device using the schemes of the cold cathode, the types of a field emitter array (FEA), a surface conduction emitter (SCE), a metal-insulator-metal (MIM), a metal-insulator-semiconductor (MIS) and a ballistic electron surface emitting (BSE) have been known.
The EED typically emits electrons by means of a quantum mechanical tunnel effect by concentrating high electric field on the emitter and accelerates the electrons emitted from the emitter by voltage applied between the cathode electrode and the anode electrode to collide with a red, green, blue (RGB) phosphor layer formed on the anode electrode, light-emitting the phosphor and displaying an image.
FIG. 1 is an exploded schematic perspective view showing a conventional flat panel display and FIG. 2 is a cross sectional view of the flat panel display taken along line I-I′ in FIG. 1. The conventional flat panel display 100 includes an image display panel 120 wherein a first substrate 121 is spaced apart from a second substrate 122. A chassis member 130 is provided at a rear side of the image display panel 120. A bottom cover 110 surrounds the rear side of the chassis member 130 and sides of the image display panel 120. A top cover 140 fixes a corner portion of a front side and is coupled to the bottom cover 110.
In the image display panel 120, the first substrate 121, which is an electron emission substrate, is spaced apart from the second substrate 122, which is an image forming substrate. A vacuum state is maintained between the first substrate 121 and the second substrate 122. A supporting member 123 is included between and supports the first substrate 121 and second substrate 122.
In the image display panel 120 a data driver 124a provides a data signal and a scan driver 124b provides a scan signal, respectively.
Significant heat is generated from the data driver 124a and the scan driver 124b when providing signals to the image display panel 120, due to a significant amount of current. The entire temperature of the panel rises as a result of the generated heat.
Heat generated during the driving of the image display panel 120 is dissipated by means of the chassis member 130 provided on the rear side.
However, when the chassis member 130 contacts only the rear side of the second substrate of the image display panel to reduce the temperature of the second substrate and, due to the typical rigidity of a spacer between the first substrate and the second substrate, non-uniformity in the temperature between the first substrate and the second substrate can result, and, in turn, cause distortion of the emission beam. The phosphor around the spacer then fails to light-emit uniformly, resulting in poor image display.